Transfer apparatus



Jan. 23, 1962 w. J. WILLIAMS ETAL.

TRANSFER APPARATUS Original Filed May 5, 1958 5 Sheets-Sheet 1 FIGB.

INV ENTOR5 Jan. 23, 1962 W. J` WILLIAMS ETAL 3 Sheets-Sheet 2 Jan- 23,1962 w. J. WILLIAMS ETAL 3,018,007

TRANSFER APPARATUS Original Filed May 5. 1958 5 Sheets-Sheet 3 PatentedJan. 23, 1952 3 Claims. (Cl. 214-1) The present invention relates totransfer apparatus for a duplex high-speed automatic article-fabricatingmachine and, more particularly, to a machine for lehring anincandescent-lamp bulb having its interior surface coated with a finelydivided light-scattering material, such as silica, and for sealing-in alament mount to such lehred bulb. The subject application is adivisional application of U.S. application Serial No. 733,077, filed May5, 1958, by William I. Williams et al.

Heretofore incandescent lamps, discharge devices and electronic tubeshave been manufactured by a group of conventional turret-type machinescomprising generally a mounting machine, a sealing-in and exhaustingmachine and a `basing machine. Specifically, in the manufacture ofincandescent lamps, a machine (of the type shown in U.S. Patent No.2,811,131, issued October 29, 1957, to S. A. Lopenslsi) has beenprovided for electrostatically coating the lamp bulbs with silica andfor lehring such coated bulbs to remove water vapor therefrom. Theseconventional machines transfer the work pieces or subassemblies fromwork station to work station either intermittently, as by indexing, orcontinuously. Because of their rotating motion and their relativelylarge weight, such conventional machines are limited by the factors ofmomentum and inertia to index speeds of about 1500 indexes per hour andproduction rates of about 1500 units per hour. Due to the stressesproduced in these conventional machines during their operation and thelimits of current engineering materials this production figurerepresents the maximum production rate for a group of such machines.With the industry contemplating production rates of 6000 units per hourit is essential that a new arrangement of the lamp manufacturing groupbe formulated and that new types of fabricating machines be substitutedfor the conventional turret-type ndexing machines.

After the electrostatically coated bulbs `are lehred on the conventionalcoating machine of the type Shown in the above-mentioned U.S. Patent No.2,811,131, at a temperature which may vary from about 400 C. up to thestrain point of the glass (which is about 480 C.) to removesubstantially all of the moisture contained therein, the Abulbs aretransferred to a conventional sealing-in and exhausting machine. Suchtransfer from the electrostatic coating machine to the sealing-inportion of the sealing-in and exhaust machine presently requires from-11 seconds and permits the lehred silica-coated bulbs to coolsufficiently whereby the silica coating absorbs moisture with occasionaldeleterious effect on the quality of the finished silica-coatedincandescent lamps.

Hence, to eliminate moisture absorption by the silica coating byreducing the transfer time and at the same time to obtain these higherproduction rates, it has been found necessary to provi-de a separate andnovel articlefabricating machine of the type shown in copending U.S.application, Serial No. 732,858, led May 5, 1958, by Hugo Bauer et al.and assigned to the same assignee as the present invention, for thesilica-coating of the incandescent lamp bulbs. ln addition, i t has beenfound desirable to combine the lehring operation with the sealing-inoperation on a novel duplex lehring and sealing-in machine of thepresent invention, thereby reducing the transfer time from the lehringoperation to the sealing-in operation to 5 6 seconds with attendantimproved quality of the resultant silica-coated incandescent lampsproduced thereby.

yIt is the general object 0f the present invention to avoid and overcomethe foregoing and other diiculties and objections to prior art practicesby the provision of transfer apparatus for a duplex article-fabricatinginachine which is capable of producing as many as 6000 units per hour.

Another object of the present invention is the provision of transferapparatus for a duplex lehring and sealing-in machine which transferapparatus is operable to transfer the lehred silica-coated bulbs fromthe lehring line to the sealing-in line with sufficient rapidity as toprevent substantial cooling of such lehred silica-coated bulbs andattendant detrimental absorption of moisture by such silica coating.

The aforesaid objects of the present invention and other objects whichwill become apparent as the description proceeds are achieved byproviding transfer apparatus for a duplex-lehring and sealing-in machineand for transferring articles from a first movable member disposed inone piane of movement to a second movable member disposed in anotherplane of movement, said transfer apparatus comprising pick-up meansoperable to move into registry with an article on said first movablemember and to remove said article therefrom, said pickup means beingfurther operable to move said article from the one plane of movement ofsaid first movable member to the other plane of movement of such secondmovable member and into registry with said second movable member and todeposit said article on said second movable member.

For a better understanding of the invention, reference should be had tothe accompanying drawings, wherein like numerals of reference indicatesimilar parts throughout the several views and wherein:

FIG. 1 is a vertical-sectional View of the transfer unit of the presentinvention for transferring lehred silicacoated bulbs from the lehringconveyor to the sealing-in conveyor, which shows one of the transferheads just closed about a lehred silica-coated bulb on the lehringconveyor and the other transfer head just opened after depositing alehred silica-coated bulb on the sealing-in conveyor.

FIG. 2 is `an enlarged fragmentary vertical-sectional view of the closedtransfer head of the transfer unit, as viewed in FlG. l, and showing thedetails of the operating mechanism for the pick-up jaws of such head andthe mechanism for vertically reciprocating such transfer heads.

FiG. 3 is a fragmentary side-elevational view, partially in section, ofthe operating mechanism for the pick-up jaws shown in FIG. l, and takenalong the line IIl-III of FlG. 2 and looking in the direction thearrows.

Fifi 4 is a horizontal-sectional view of the transfer unit along theline lV-IV of FIG. 1 in the direction of the arrows.

FIG. 5 is a view showing the drive means for the sealing-in conveyor andthe drive means for the other transfer device for transferring sealed-inlamps from the sealing-in conveyor to the exhaust machine, such transferdevice being shown in the down position ready to remove a sealed-in lampfrom the sealing-in conveyor and to deposit another sealed-in lamp inthe exhaust machine.

Although the principles of the transfer apparatus of the presentinvention are broadly applicable to a duplex article-fabricatingmachine, the transfer apparatus of the present invention is particularlyadapted for use in conjunction with apparatus for the lehring ofsilica-coated bulbs and the sealing-in of filament mounts to such lehredsilica-coated bulbs, and hence it has so been illustrated and will be sodescribed.

With specific reference to the form of the invention illustrated in thedrawings, and referring particularly to FIG. 4, it will be noted that itis extremely essential for the production of a quality silica-coatedlamp that the silica-coated bulbs 22, which are raised to a temperatureof 425 450 C. by the lehring oven, not shown, be transferred by thetransfer unit 36 from station 22' on the lehring conveyor 31 (FIG. l) tostation Ia' on the sealing-in conveyor 38 as rapidly as possible, sothat the temperature of such heated silica-coated bulbs (during suchtransfer) will not fall below 350 C. be-

vfore such bulbs reach the sealing-in fires (not shown) and the heatingfires (not shown), thereby eliminating the possibility of the lehredsilica-coated bulbs 22 reabsorbing moisture during such transfer. Thefive indexes of the lehring and sealing-in machine required toaccomplish this (consuming 5 1.2 or 6.0 seconds) includes the index tothe station before station 22', an idle station on the lehring conveyor32; the 4index to station 22' where the transfer unit 36 picks up thelehred silica-coated bulb 22;

ltwo indexes required for such transfer unit 36 to move through positionC (FIG. 4) and into registry with a sealing head 37 at station Ia' (FIG.4) to deposit the lehred silica-coated bulb 22 over a filament mount onsuch sealing head 37; and the index to the station after lstation 1a,where the lehred silica-coated bulb 22 enters sealing fires (not shown)and heating fires (not shown).

Transfer unit This transfer unit 36 (FIGS. 1-4) is operative to transfera lehred silica-coated bulb 22 from the transfer station 22' on thelehring conveyor 32 to the bulb-receiving station 1a on the sealing-inconveyor 38.

This transfer unit 36 is pro-vided with a rotatable sleevelike body 258(FIGS. 1 through 4) of generally rectangular cross-section and mountedon a rod 260 depending from a yoke 262 (FIG. 1) and having its lower endsecured in a bracket 263 on the bottom cover plate 80 (FIG. 5). The yoke262 is supported on mount rods 254 and 266 having their lower portionsupstanding from brackets 267 on the table 58 and a projecting portion ofthe bracket 158, respectively.

The transfer unit 36 is provided with four transfer heads 270quadrantally disposed on the body 258 (FIG. 4). For the purpose ofreciprocably mounting an upper casting 272 of each transfer head 270(FIGS. 1 and 2) with respect to the body 258, a dove-tail slide portion274 of`such upper casting 272 is slidably fitted into a l suitable guidein the body 258 (FIGS. 1 and 2). To provide means for slidably mountinga lower casting 276 of Veach transfer head 270, -a hollow sleeve 278having a lower collar 279, as viewed in FIGS. 1 and 2, depends from vtheupper casting 272, and the lower casting 276 is s-lidable on the lowerportions of such hollow sleeve 278.

The lower casting 276 is normally biased into abutting engagement withthe upper casting 272 (FIG. l) by tension springs 280 extendingtherebetween and resilient means are provided for engaging the dome of alehred bulb 22. Such means may comprise a cup 282 mounted on the lowerend of a rod 283 reciprocable in the hollow 278 (FIGS. 1 and 2) isprevented by a roller 288 carried vthereby and which rides in a verticalslot provided in the Y'slide portion 274 of the upper casting 272.Bulb-gripping means for each of the transfer heads 270, is provided inthe form'of three fingers 292V which are pivoted on projections of thecollar 279 on the hollow sleeve 278. Such bulb-gripping fingers 292 areoperated by movement of the lower casting 276, through rollers 2% amxedthereto which engage a cam surface 298 at the end of casting 276, asviewed in FIG. 2, with such rollers 296 being biased into engagementwith the cam surface 298 by a circular compression spring 299.

In order to index the transfer heads 270, in counterclockwise direction(as viewed in FIG. 4) every 1.2 seconds in synchronism with thesealing-in conveyor 38, an indexing mechanism (not shown) is providedfor the transfer unit 36, which indexing mechanism is identical to anindexing mechanism 300 (FIG. 5) for the transfer unit 35, and whichmechanism 300 is driven from the vertical shaft 152 (FIG. 5) of theindexing mechanism for the sealing-in conveyor 38. Although the indexingmechanism for the transfer unit 36 (FIGS. 1-4) is not shown, itsconstruction and operation can be clearly understood from aconsideration of the identical indexing mechanism 300 for the transferunit 35.

Indexing mechanism As shown in FIG. 5, a gear 302 on the vertical shaft252 of the indexing mechanism 140 for the sealing-in conveyor 38 isconnected by a gear train 303 to a gear 304 (FIGS. 1 and 5) secured tothe body 258 of the transfer unit 35. Y

Thus, every 1.2 seconds, the counterclockwise rotation (FIG. 5) of theVertical shaft 152 by the indexing mechanism 140 for the sealing-inconveyor 38 is transmitted through the above-described gear train 303 tocause 90 counterclockwise rotation of the gear 304 on the body 258 ofthe transfer unit 35 with attendant 90 rotation of the transfer heads270 (FIG. 4).

Referring again to the transfer unit 36 (FIGS. 1-4) it will beunderstood that when a transfer head 270 is indexed, for example, intoregistry with a lehring head 31 at station 22' (FIG. l) of the lehringconveyor 32, such transfer head 270 is in the up position with thelo-wer casting 276 in abutting engagement with the upper casting 272 andthe bulb-gripping fingers 2.92 are then in their open position. Atstation 22' a roller 32? (FIGS. 1 and 2) on the upper casting 272engages a yoke 322 of the reciprocating mechanism 324 for the transferhead 270 (FIG. 2). Such reciprocating mechanism 324 lowers the transferhead 270 a distance d to the solid-line position shown in FIG. 1 andcauses the bulb-gripping fingers 292 to close about the lehredsilicacoated bulb 22 on the lehring head 3ft at station 22.

Reciprocating mechanism for transfer head at station 22' Thereciprocating mechanism 324 for the transfer head 270 is mounted on abracket 326 (FIG. l) carried by the mount rod 266 (FIG. 1) of themachine frame. The yoke 322 is affixed to a first operating slide 328(FIG. 2) reciprocally movable on the bracket 326 which causes likemovement of the transfer head 270, with this first operating slide 328frictionally engaging a second operating slide 330 also movable in aguide on the bracket 326, for operating the bulb-gripping fingers 292.These operating slides 328 and 330 are reciprocated by an operatinglever 332 (FIGS. 2 and 4) connected to the lower end, as viewed in FIG.2, of the second operating slide 330 and such operating lever 332 isaffixed to a horizontal shaft 334 (FIG. 4) journalled in bearings 336projecting from the brackets 326. A lever 338 on the left-hand end ofthe horizontal shaft 334, as viewed in FIGS. l and 4, is in turn joinedby a connecting rod 340 to one end of a lever 342 pivoted at on abracket 346 affixed to the table 58 (FIG. l). A link 348 connects theother end ofthe lever 342 with a bell-crank lever 350 also pivoted at352 to the bracket 346, which bellcrank lever 350 has its rollercarrying end in engagement with a box cam 354 on the aforementionedshaft 230 (FlG. 1).

The counterclockwise rotation of the box cam 354, as viewed in FIG. 1,is transmitted through the abovedescribed conventional linkage to theoperating lever 332 to cause downward movement of the operating slides330 and 328. Such downward movement of the first operating slide 32Scarrying the yoke 322 causes the roller 321i) engaging the yoke 322 toalso move downwardly with attendant corresponding movement of thetransfer head 274D. The first operating slide 323 moves downwardly withthe operating slide 33t) a distance d (FGS. 1 and 3) until such rstoperating slide 32S engages an adjustable stop 356 (FIG. 3) atiixed bymeans of a plate to the lower portions of the bracket 326. In this downposition of the transfer head 27d, the bulb-gripping ngers 292 arejuxtaposed about a lehred silica-coated bulb 22 on the lehring head 3land the cup 232 has resiliently engaged the dome of such bulb 22, suchas shown by the position of the transfer head 27% above the sealing-inhead 37 in FIG. 1.

The continued downward movement of the second operating slide 336, adistance db FiG. 3 (caused by the continued rotation of the operatinglever 332, in clockwise direction about the horizontal shaft 334, asviewed in FIGS. 2 and 4,) causes a cam 358 (FIGS. 2 and 3) carried bythe second operating slide 33t) to engage a roller 363 of a mechanismfor opening and closing the bulb-gripping fingers 292. Such roller 36@is carried by a common pivot 362 for links 364 and 366, which are alsoindividually pivoted at 36S on the upper casting 272 and the lowercasting 276 (FiG. 2). Engagement of the cam 353 with the roller 26dmoves the links 36d and 366 to the left from the dotted-line positionshown in FIG. 3, to the dash-line position indicated therein, withattendant movement of the lower casting 276 away from the upper casting272 (against the action of spring 236). This movement of the lowercasting 276 causes its cam surface 298 to move the rollers 296 on thebulb-gripping fingers 292 outwardly with resultant closure of suchfingers 292 about the lehred silicacoated bulb 22 on the lehring head 3lat station 22.

The box cam 354 (through the above-described conventional linkage) thenreverses the direction of rotation of the operating lever 332 causingthe second operating slide 33t to move upwardly the distance db asviewed in FlG. 3, and to engage a stop 372 carried by the rst operatingslide 328. The operating slide 328 and 33h thereafter move upwardlytogether (along with the now yloaded transfer head 270) the aforesaiddistance "d thereby removing the lehred silicia-coated bulb 22 from thelehring head 3i preparatory for indexing of such now loaded transferhead 276 from a position in registry with a lehring head 31 at station22' of the lehring conveyor 32 to position C (FIG. 4) by the indexingmechanism (not shown) for the transfer unit 36.

It will be understood that during the upward movement of the secondoperating slide 333, the cam 353 carried thereby does not engage theroller 36) of the mechanism for operating the bulb-gripping jaws 292,because such roller 36d is out of the path of movement of said cam 353in the position shown by the dash-lines of FIG. 3, and such jaws remainclosed about the lehred silicacoated bulb 22.

As the loaded transfer head 276 lea es station 22' of the lehringconveyor 32, the roller 32d of such transfer head 27@ rolls off the yoke322 and onto a registering annular stationary descending cam track 374(FiGS. 1 and 3). This cam track 374 extends from the yoke 322 at station22, through position C and to a similar yoke 322 of another'reciprocating mechanism 32d for the transfer head 27@ while such head isat station lcz of the sealing-in conveyor 33, with such cam track 37dbeing utilized to lower the now loaded transfer head 270 from the upposition adjacent the lehring conveyor 32 to the up position adjacentthe sealing-in conveyor 3S.

Reciprocating mechanism for transfer head at station Ia Since themechanism 324' for reciprocating the transfer head 270 (while suchtransfer head is in registry with a lamp mount on a sealing-in head 37at station la of the sealing-in conveyor 38) is similar in structure tothe reciprocating mechanism 374 it is deemed unnecessary to describe itin detail. Accordingly, it should be sutiicient to say that thisadditional reciprocating mechanism 324 has its bulb-gripping lingers 292(FIG. l) operated by a connecting rod 375 extending from a bell-cranklever 376 pivoted at 344 and which lever 376 is connected by a link 378to a second bell-crank lever 38) pivoted at 352 with the roller carryingend thereof engageable with a box cam 354 (FIG. 1'), on the aforesaidshaft 230. Shortly after the roller 326 on the transfer head 27@ engagesthe yoke 322 juxtaposed above station 1a, the reciprocating mechanism324 moves the transfer head 270 and the lehred silica-coated bulb 22downwardly, as viewed in FIG. 1, a distance D to deposit the lehred bulb22 on the sealing-in head 37 therebeneath and to again rise to itsinitial position, with the entire operation of the transfer head 270 atthe station ia' above the sealing-in conveyor 38 being identical to thatpreviously described when such transfer head 274i was at station 22'except that the cam 358 moves the roller 366 to the dotted-line position(FIG. 3) to open the fingers 292. Upon completion of its operation atstation la the reciprocating mechanism 324' will have raised the emptytransfer head 270 upwardly a distance D, so that its roller 320 is thenpositioned in registry with an ascending stationary elevating cam track374- (FIG. 3), extending from the yoke 322', at station la throughposition E again to the yoke 322 at station 22. As the roller 320 ridesup the cam track 374 the now empty transfer head 270 is elevated fromits up position adjacent station la (during the next two indexes of thetransfer unit 36) to its up position at station 22, whereupon theabove-described transfer cycle is repeated.

It will be recognized by those skilled in the art that the objects ofthe present invention have been achieved by the provision of transferapparatus for a duplex lehring and sealing-in machine which is capableof producing 6000 units per hour. Specifically, the transfer apparatusfor the duplex machine is operable to rapidly transfer the lehredsilica-coated bulbs from the lehring line to the sealing-in line,thereby preventing substantial cooling of such lehred bulbs which wouldotherwise result in absorption of moisture by such silica-coating.

While in accordance with the patent statutes one best known embodimentof the invention is illustrated and described in detail, it is to beparticularly understood that the invention is not limited thereto orthereby.

We claim:

1. Apparatus for transferring articles from a first movable memberdisposed in one plane of movement to a second movable member disposed inanother plane of movement, comprising a body, an upper casting rotatablewith and reciprocable in said body, a pick-up head carried by said uppercasting and disposed in a first reference plane, a lower castingreciprocable with respect to said upper casting and said pick-up headand rotatable therewith, operating means connecting said upper castingand said lower casting and operable to reciprocate said lower castingwith respect to said upper casting and said pick-up head, said pick-uphead being operable by movement of said lower casting with respect tosaid upper casting to close about an article, means connected to saidbody for indexing the pick-up head through a plurality of work stationsincluding a pick-up station adjacent said first movable member and adischarge station adjacent said second movable member, cam meansdisposed between said pick-up station and said discharge station andengageable by said pick-up head during movement of the lattertherebetween, said cam means being operable to move said pick-up headfrom said first reference plane to a second reference plane, a firstslide means at such pick-up station engageable by said upper casting, asecond slide frictionally engageable with said first slide, a firstldrive means connected to said second slide and operable to causemovement of said pick-up head from said first reference plane and towardsaid first movable member to juxtapose such pick-up head about anarticle on said first movable member, a first stop means engageable bysaid first slide to `prevent further movement of said upper'casting andsaid pick-up head, said first drive means being further operable to thenmove said second slide thereby actuating said operating means andcausing movement of said lower casting relative to said upper casting tocause attendant securing of such article by such pickup head, andreciprocating means at said discharge station engageable by said uppercasting and operable to cause movement of said pick-up head from saidsecond reference plane toward said second movable member with attendantdeposition of the article o'n said second movable member, said secondreciprocating means being further operable to actuate rsaid operatingvmeans and cause said pick-up head to release such article deposited onthe second movable member.

2. Apparatus for transferringarticles from a first movable rnemberdisposed in one plane of movement to a second movable member disposed inanother plane of movement, comprising a body, an upper casting rotatablewith and reciprocable in said body, a pick-up head carried by said uppercasting and disposed in a first reference plane, a lower castingreciprocable with respect to said upper casting and said pick-up headand rotatable therewith,'operating means connecting said upper castingand said lower casting and operable to reciprocate said lower castingwith respect to said upper casting and said pick-up head, said pick-uphead being operable bymovement of said lower casting with respect tosaid upper casting to close about an article, means connected to saidbody for indexing the pick-up head through a plurality of work stationsincluding a pick-up station adjacent said first movable member and adischarge station-adjacent sai-d second movable member, cam meansdisposed between said pick-up station and said discharge station andengageable by said pick-up head during movement of the lattertherebetween, said cam means being operable to move said pick-up headfrom said first reference plane to a second reference plane, a rst slidemeans at such pick-up station engageable by said upper casting, a secondslide frictionally engageable with said first slide, a first drive meansconnected to said second slide and operable to cause movement of saidpick-up head from said first reference plane and toward said rst movablememger to juxtapose such pick-up head about an article on said firstmovable member, a first stop means engageable by said first slide toprevent further movement of said upper casting and said pick-up head,said first drive means being further operable to then move said secondslide, thereby actuating said operating means and causing movement ofsaid lower casting relative to said upper casting to cause attendantsecuring of such article by such pickup head, a third slide at saiddischarge station engageable by said upper casting, a fourth slidefrictionally engageable with said third slide, and a second drive meansconnected to said Second slide and operable to cause movement of saidpick-up head from said second reference plane and toward said secondmovable member with attendant deposition of the article on said secondmovable member, a second stop means engageable by said third slide toprevent further movement of said upper casting and said pick-up head,said second drive means being further operable to then move said fourthslide thereby actuating said operating means and causing said pick-uphead to release such article deposited on the second movable member.

3. Apparatus for transferring articles from a first movable memberdisposed in one plane of movement to a second movable member disposed inanother plane of movement, comprising a body, an upper casting rotatablelwith and reciprocable in said body, a pick-up head carried by saidupper casting and disposed in a first reference plane, a lower castingreciprocable with respect to said upper casting and said pick-up headand rotatable therewith, operating means connecting said upper castingand said lower casting and operable to reciprocate said lower castingwith respect to said upper casting and said pick-up head, gripping meanspivote/d on said pick-up head andrengageable by said lower casting, saidgripping means being operable by movement of said lower casting withrespect to said upper casting to close about an article, means connectedto said body for indexing the pick-up head through a plurality of workstations including a pick-up station adjacent said first movable memberand a discharge station adjacent said second movable member, cam meansdisposed between said pick-up station and said discharge station andengageable by said pick-up head during movement of the lattertherebetween, said cam means being operable to move said pick-up headfrom said first reference plane to a 'second reference plane, a firstslide at such pick-up station engageable by said upper casting, a secondslide frictionally engageable with said first slide, a first drive meansconnected to said second slide and operable to cause movement of saidpick-up head from said first reference piane and toward said firstmovable member to juxtapose such gripping means "about an article onsaid first movable member, a first stop means engageable by said firstslide to prevent further movement of said upper casting and said pick-uphead, said first drive means being further operable to then move saidsecond slide, thereby actuating said operating means and causingmovement of said lower casting relative to said upper casting to causeattendant securing of such article by such gripping means, a third slideat said discharge station engageable by said upper casting, a fourthslide frictionally engageable with said third slide, and a second drivemeans connected to said fourth slide and operable to cause movement ofsaid pick-up head from said second reference plane and toward saidsecond movable member with attendant deposition of the article on saidsecond movable member, a second stop means engageable by said thirdslide to prevent further movement of said upper casting and said pick-uphead, said second drive means being further operable to then move saidfourth slide thereby actuating said operating means and causing saidgripping means to release such article de- .posited on the secondmovable member.

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